The task of authenticating or verifying the identity of a user requires a certain level of security in addition to the method by which the user is identified. A typical authentication system involves, for example, a user who has a smart card or perhaps simply a credit card. When the user presents himself or herself to the system, such as at an automatic teller machine (ATM), the user presents his or her credit card, which identifies the particular user by name and account number. The user then presents his or her personal identification number (PIN), or similar information known only to the user, and the presented information is sent to a host computer. The host computer, which is based on a database, can then identify the user by the user's name and, for example, by the particular PIN that the user is supposed to use.
In the case when biometrics are used for authentication, the identification of the user can be done by presenting a biometric such as a fingerprint, the user's face, or the user's voice, to the system. In addition to that, when the user identifies himself or herself by presenting a biometric, such as a fingerprint, the system goes through the process of looking at a stored template of the user's fingerprint which was created in advance. The system compares the user's presented fingerprint to the stored template and verifies that this is the same person, making its decision based on certain predefined parameters, such as threshold of match scores between the presented and stored biometric samples.